PIEZO-ELECTRIC RESONANT VIBRATOR FOR A SELECTIVE CALL RECEIVER

摘要

A piezoelectric resonant vibrator (206) is described comprising a resonant armature (2) having a centrally located weight (604), and at least four planar circular spring members (22, 24, 26, 28) which provide a restoring force normal to the movement of the weighted armature (2) within a non-magnetic housing (614) which encloses and supports the armature (2). A piezo-electric driver element (602) is coupled to the armature (2) for inducing movement of the armature (2) at a predetermined resonant frequency. A ferromagnetic plate (612) is mounted to the housing (622) and magnetically couples to a magnet (610) which is coupled to the weight (604) to maintain tension on the armature (2) when an excitation signal is not supplied to the piezo-electric driver (602), and the armature (2) is at equilibrium.